A new material to unearth mysteries of magnetic fields

Journeying to the center of the Earth, a la Jules Verne, won’t be happening anytime soon. A new material made from a liquid metal and magnetic particles, however, could make it much easier for researchers to recreate the powerful forces at the planet’s core.

“We can potentially reproduce some of the phenomena seen in planets and stars with this material,” said Eric Brown, assistant professor of mechanical engineering and materials science at Yale and senior author of a study published Jan. 30 in the journal Physical Review Fluids.

The new material is made from an alloy of indium and gallium (eGaIn) with various particles suspended within it. When flowing, its ability to generate or modify magnetic fields is up to five times greater than that of pure liquid metal. That, along with a significant increase in electrical conductivity, means researchers can use the material to study the effects of magnetohydrodynamics (MHD)—the magnetic properties of conductive fluids usually only observable in the cores of planets and stars.

One challenge of suspending particles in liquid metals is that the air oxidizes the skin of the metals, keeping particles on the surface. The researchers got around this by submerging the liquid metal in an acid solution, which removes and prevents oxidation.